I know they're not intended to be creepy, but for some reason I find most of the very early Merrie Melodies cartoons from the 30s (pre-cursors to what became Looney Tunes) which were in Black & White and featured a lot of singing/dancing, creepy as hell. I love vintage 'toons from the 40s and 50s but those really early 'toons have aged so badly that they look like transmissions from some bizarre netherworld nowadays.

Ah, those are the best kind of creepy cartoons!

Do a web search for Van Bueren studios, a 30's animation stuio which spun off of Aesop's Fable's Studios. Weird, Weird stuff, their worst cartoons are probably their "Milton and Rita mouse" cartoons. Milton and Rita look exactly like some other, more famous mice, but with worse animation, and adult situations. They also have a "Tom and Jerry." No, these weren't a rip-off of Hanna Barbera's characters, Van Bueren was gone long before the famous cat and mouse team came about. Just look them up. It's strange, strange stuff.

Ozzymandias speaks: Van Bueren cartoons are some of the worst. They feature animals that all look like Mickey Mouse. Most of them don't make any sense or go nowhere. I've only seen two I really like. One was the Snowman, in which a snowman comes to life and starts terrorizing little animals. It was supposed to cash in on the trend of horror movies at the time. Another is a cartoon about cupid's army and an old batchelor that looks like W.C. Fields and an old spinster. It was banned from TV because the cupid's don't have pants (or genitalia either).

The cupid cartoon came out later, after they had hired some of Disney's ex-animators, after their animation had improved. Disney eventually got RKO to distribute his cartoons. Since Van Bueren was with RKO, Van Bueren found themselves with out a distributor. They decided to give up, sell off their cartoons, and ask Paul Terry for a job.

Around the same time they made 3 Felix the cat cartoons , which are a staple of arguably-public-domain-cartoon-collections. I liked these cartoons when I was younger.

Rotoscoped animation does look weird to me, also, but there is something a bit extra freaky with that colormation stuff. I think it was the odd lack of details - except for those vivid toothy mouths - in the faces.

I recently found out about this one thanks to cracked.com. It's a cartoon from Finland called The Moomins Its stop motion about a happy couple of hippos, some funny little creatures and THE LIVING EMBODIMENT OF ETERNAL SORROW!!! The creature is called the groke. Anything it touches dies. It moves and looks like some horrible phantom. On the other hand-it would have made for an awesome villain for some Rankin-Bass Halloween special.

I agree about the pre-Looney Tunes cartoons, they are nowhere near as good as the ones from the 40's-60's. Bugs Bunny with that tiny little head and an obese Elmer Fudd. What about early Daffy Duck, he acted like he was on crack. I get that same creepy feeling when I watch those early Simpsons shorts from The Tracy Ullman show.

Gumby in a messed-up, copyrighted friendly take off of The Little Prince. If I'm not mistaken, one of the characters from Davey and Goliath makes a guest appearance. Edit: This one is actually from the 60's.